http://www.techradar.com/news/nintendo-switch-has-triple-the-games-now-that-wii-u-had-in-its-entire-lifetime

Though it hasn’t been on the market for long, the Nintendo Switch has been markedly more successful than its predecessor, the Wii U. In just 11 months, more Switch consoles were purchased than Wii U consoles over five years. 

While there isn’t one single thing that can be identified as the reason for the console’s success, the fact that the Switch has had as many games in nine months as the Wii U did in over two years probably has something to do with it.